LAS VEGAS — Vice President Harris on Tuesday afternoon offered a full-throated defense of President Biden as he continues to fight for his reelection bid while she is on the road this week to energize key parts of the Democratic coalition.

“We always knew this election would be tough, and the past few days have been a reminder that running for president of the United States is never easy,” Harris said at a Biden campaign event focused on Asian American, Native Hawaiian and Pacific Islander voters. “But the one thing we know about our president, Joe Biden, is that he is a fighter and he is the first to say, when you get knocked down, you get back up.”

Harris was met with loud applause from the diverse crowd of several hundred attendees.

Harris’s remarks are the most vocal defense she has offered of the president before a group of voters since Biden’s faltering debate performance last month. Since the June 27 debate, Harris has been under an unusual spotlight as she seeks to bolster Biden’s candidacy while also showcasing her own talents as a campaigner.

Harris’s visit to Las Vegas is part of the campaign’s outreach to AANHPI voters, a small but vital group. She spoke shortly after lawmakers 2,400 miles away in D.C. met to discuss Biden’s campaign amid calls from some within his party for him to step aside.

Harris’s campaign swing — she visits Dallas on Wednesday and Greensboro, N.C., on Thursday — comes as some Democrats weigh the possibility that she could become their presidential nominee if Biden steps aside. While Biden has repeatedly said he will remain in the race, many Democrats consider Harris the only realistic replacement should he drop his candidacy.

That leaves the vice president with dual, delicate and potentially contradictory goals this week: strengthening Biden at a deeply vulnerable moment of his political career while also demonstrating her own potential appeal. With Biden in Washington seeking to tamp down any rebellion in Congress, Democrats will be closely watching Harris in the coming days to gauge her abilities as a campaigner, especially after an ill-fated presidential run in 2020.

“There’s no playbook for this. She’s walking on a fresh, unwalked trail,” said Mike Trujillo, a Democratic strategist and former aide to Hillary Clinton. He underscored how unprecedented it is for Democrats to be discussing the status of their presumptive nominee just weeks before the Democratic National Convention, which begins Aug. 19.

“This is a massive test to prove her mettle in terms of her loyalty to the president, her loyalty to the White House, her loyalty to the policy agenda that this White House has set forth, loyalty to the campaign and a loyalty to our democracy,” Trujillo added. “She has not made a single mistake.”

The Biden campaign has long seen Harris as a potent messenger in reaching Black and Asian American voters, an asset that has become more important as the president scrambles to shore up his support from these influential groups. In 2020, exit polls showed Biden winning Black voters by 75 percentage points and Asian American voters by 27 points, and any faltering enthusiasm among them could be devastating in a close race against presumptive Republican nominee Donald Trump.

Harris’s mother was an Indian immigrant, and her father came from Jamaica. Her ascent has been a point of pride in Black and Asian communities.

Her trip to Las Vegas marked her sixth visit this year to Nevada, a battleground state that Biden won by fewer than 34,000 votes in 2020 and that recent polls suggest could be slipping from the Democrats’ grasp.

After praising Biden, Harris hammered on the campaign’s argument that a second term for the former president would be disastrous. Trump wants to turn the United States into a dictatorship, she said, “and the Supreme Court basically just declared he can get away with it.” That was a reference to a recent decision saying Trump is immune from prosecution for his official acts as president.

“Someone who vilifies immigrants, who promotes xenophobia, someone who stokes hate should never again have the chance to stand behind a microphone and the seal of the president of the United States,” she said.

Harris was joined by Padma Lakshmi, an Indian American author and television host, who touted Harris as the first female vice president and blasted Trump in her brief remarks.

Ahead of the appearance, the Asian American Action Fund, a Democratic-aligned PAC, described Harris’s appearance as a “community celebration to recognize the accomplishments that President Biden and Vice President Harris have delivered for the AANHPI community — and all Americans!”

Harris remains a vociferous defender of Biden, urging voters to focus on the dangers of a second Trump term. A day after the June debate, Harris was also in Las Vegas for a rally, where she sought to defend the administration’s record and neutralize concerns about Biden, depicting him as a leader and Trump as a liar.

“This race will not be decided by one night in June,” she said that day, seizing on what has become her central message — that Biden may have had a bad debate night but that he is a great president, and his performance does not reflect deeper problems with his health or competence.

Few if any communities are as important to any Democrat’s national aspirations as Black voters, especially Black women, whose embrace of Biden in 2020 catapulted him to the nomination and the presidency. Harris spent Saturday at the Essence Festival in New Orleans, speaking to a crowd of mostly Black women in a moderated conversation that focused heavily on the stakes of the election but did not touch on the current controversy surrounding the Democratic Party and its standard-bearer.

The vice president’s multiday trip this week includes an address to the historically Black sorority Alpha Kappa Alpha Sorority Inc. on Wednesday in Dallas. Harris, who graduated from Howard University in 1986, is a member of AKA, giving her access to a powerful network of engaged activists.

On Thursday, Harris heads to Greensboro, her sixth trip to North Carolina, which Democrats are attempting to flip blue this election. Next week, she will meet in Indianapolis with members of Zeta Phi Beta, another historically Black sorority with a record of focusing on social justice.

Moderated or even scripted events like the ones Harris is participating in this week have allowed her to make a campaign pitch to key voters without having to contend with the pointed questions that have arisen following Biden’s rocky debate performance.